The article discusses the mutual interaction and inspiration between avant-garde art and children as producers of texts and images in the 1920s through the 1940s. The key example is the Danish picture book Urskov-Æventyr (Jungle adventure, 1944), written and illustrated by the seven-year-old girl Ileana Holmboe. Holmboe won the first prize in a children’s competition for making the best picture book, and the book was published shortly after. The theoretical framework is the idea of children as co-producers of texts and the so-called “kinship-model” proposed by Marah Gubar (Art-ful Dodgers; “Risky Business”) which was further developed by Victoria Ford Smith. The analysis of Urskov-Æventyr focuses on the agency of the child narrator and the child reader, especially on how the narrator becomes a kind of stage director in relation to the narrative, and on the co-production between child author and adults engaged in the process. Furthermore, the article describes a loop in the production of avant-garde art and picture book, where avant-garde artists seek inspiration in children’s drawings and their “spontaneous” and “natural” modes of expression, while Ileana Holmboe also seems to have been inspired by avant-garde author Jens August Schade and avant-garde author and painter Hans Scherfig’s picture book Urskoven (The jungle, 1937). The article concludes that children’s literature studies would benefit from paying more attention to the co-production and interaction between adults and children in relation to children’s literature in general, and especially in relation to picture books in this period.